A device that performs illumination by guiding light emitted from a light source are required in various ways for lighting lamps, lamps for vehicles, and liquid crystal displays. A technology of making the structure of equipment thin, and a structure that can increase light efficiency are considered as the most important technologies in lighting apparatus.
A liquid crystal display equipped with the lighting apparatus is exemplified and described as follows.
Referring to FIG. 1, in a lighting apparatus 1, a flat light guide plate 30 is disposed on a substrate 20 and a plurality of side type LEDs 10 (only one shown) is arrayed on the sides of the light guide plate 30.
Light L entering the light guide plate 30 from the LEDs 10 is reflected upward from a fine reflection pattern or a reflective sheet 40 under the light guide plate 30 and travels out through the light guide plate 30, such that an LCD panel 50 above the light guide plate is provided with light.
In the structure of the lighting apparatus, as shown in the conceptual view of FIG. 2, a plurality of optical sheets, such as a diffusion sheet 31 or prism sheets 32, 33, or a protective sheet 34, may be further disposed between the light guide plate 30 and the LCD panel 50.
Accordingly, since the light guide plate is basically used as a necessary component in the lighting apparatus, there is a limit in reducing the entire thickness of a product due to the thickness of the light guide plate, and the image quality decreases in a lighting apparatus with a large area.